diff options
| author | Ryosuke Yasuoka <ryasuoka@redhat.com> | 2024-05-19 18:43:03 +0900 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-05-20 11:41:26 +0100 |
| commit | e4a87abf588536d1cdfb128595e6e680af5cf3ed (patch) | |
| tree | 687f63f649607a861f24260e842a08c4f3852e95 /net/nfc | |
| parent | cc563e749810f5636451d4b833fbd689899ecdb9 (diff) | |
nfc: nci: Fix uninit-value in nci_rx_work
syzbot reported the following uninit-value access issue [1]
nci_rx_work() parses received packet from ndev->rx_q. It should be
validated header size, payload size and total packet size before
processing the packet. If an invalid packet is detected, it should be
silently discarded.
Fixes: d24b03535e5e ("nfc: nci: Fix uninit-value in nci_dev_up and nci_ntf_packet")
Reported-and-tested-by: syzbot+d7b4dc6cd50410152534@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d7b4dc6cd50410152534 [1]
Signed-off-by: Ryosuke Yasuoka <ryasuoka@redhat.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/nfc')
| -rw-r--r-- | net/nfc/nci/core.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c index b133dc55304c..7a9897fbf4f4 100644 --- a/net/nfc/nci/core.c +++ b/net/nfc/nci/core.c @@ -1463,6 +1463,19 @@ int nci_core_ntf_packet(struct nci_dev *ndev, __u16 opcode, ndev->ops->n_core_ops); } +static bool nci_valid_size(struct sk_buff *skb) +{ + BUILD_BUG_ON(NCI_CTRL_HDR_SIZE != NCI_DATA_HDR_SIZE); + unsigned int hdr_size = NCI_CTRL_HDR_SIZE; + + if (skb->len < hdr_size || + !nci_plen(skb->data) || + skb->len < hdr_size + nci_plen(skb->data)) { + return false; + } + return true; +} + /* ---- NCI TX Data worker thread ---- */ static void nci_tx_work(struct work_struct *work) @@ -1516,7 +1529,7 @@ static void nci_rx_work(struct work_struct *work) nfc_send_to_raw_sock(ndev->nfc_dev, skb, RAW_PAYLOAD_NCI, NFC_DIRECTION_RX); - if (!nci_plen(skb->data)) { + if (!nci_valid_size(skb)) { kfree_skb(skb); kcov_remote_stop(); break; |